Bowling pin with flexible belly



Oct. 10, 1967 w. H. SCHIMANSKI ET AL 3,346,258

BOWLING PIN WITH FLEXIBLE BELLY Filed May 18, 1964 IIDL c KUL $5, M O RTA C M mmwm H WCfi W D 1 M mMm wm u um M United States Patent 3,346,258BOWLING PIN WITH FLEXIBLE BELLY William H. Schimanski, Woodland Hills,Calif, and Michael G. Gantraud, Mnskegon, and Fred E. Satcheli, GrandHaven, Mich, assignors to Brunswick Corporation, a corporation ofDelaware Filed May 18, 1964, Ser. No. 368,684 2 Claims. (Cl. 273-82)ABSTRACT OF THE DESCLOSURE A bowling pin having a hollow metal core anda plastic coating over the core. The core has weakened areas above andbelow the impact area in the belly of the pin so that the belly flexesinward under impact with a bowling ball to increase the impact time.

The disclosure This invention relates to an article having a hard coreand intended for use under conditions wherein the core is subjected toimpact forces. More particularly, this invention relates to bowling pinshaving hollow, rigid cores and to the scoring characteristics of suchpins.

It is a general object of this invention to provide a new and usefularticle of manufacture including a novel hollow, hard core member of aconfiguration providing a desired flexibility in the article ofmanufacture.

It is another object of this invention to provide new and useful bowlingpins having hollow, hard cores and having improved scoringcharacteristics.

Still another object of this invention is to provide a new and usefulbowling pin core which is generally rigid, but flexible in the bellyregion under impact conditions.

Yet another object of this invention is to provide a bowling pin havinga generally rigid, hard inner core with sufiicient flexibility in thebelly region to extend the contact time of an impacting bowling ball.

Further objects will become readily apparent from the following detaileddescription taken in connection with the accompanying drawing, in which:

The figure is a vertical section through an embodiment of a bowling pinof this invention.

While an illustrative embodiment of the invention is shown in thedrawings and will be described in detail herein, the invention issusceptible of embodiment in many different forms, and it should beunderstood that the present disclosure is to be considered as anexemplification of the principles of the invention and is not intendedto limit the scope to the embodiment illustrated.

Illustrative of articles of manufacture provided by the presentinvention having hard cores which receive impacts during use, arebowling pins which are intended to be used in bowling games, such astenpins, and are to be struck by a ball in the manner normally occurringduring such bowling games. In general, this invention providesflexibility in the impact area of the article under impact conditions,giving a longer contact time. In the instance of bowling pins, aplastic-coated hollow metal core generally has scoring characteristicsdifferent from those of a maple core pin and show very definite scoringweaknesses in both the thin and heavy-hit areas in the game of tenpins.

Before a synthetic pin, such as the plastic-coated hollow metal corepin, can receive approval of the American Bowling Congress, the majorregulatory body with respect to bowling pin specifications, the pin mustscore like a sound, hard maple pin. Thus, the hard maple pin isconsidered as the standard in the bowling industry.

The increased impact time, provided by the greater flexibility in thebelly region of the core in bowling pins ICC prepared in accordance withthe present invention, results in improving the scoring characteristicsof the pins for bringing them more in line with the scoringcharacteristics of a maple pin. Additionally, the longer contact timepermits transfer of the force from the ball under impact over a longerperiod of time, resulting in improved durability and improved soundcharacteristics.

Referring now to the figure, there is illustrated an embodiment of theinvention including a bowling pin core with a flexible belly. Thebowling pin has a hard, hollow core 12 made of a hard material, e.g., alight-weight metallic material such as aluminum, magnesium, alloys ofaluminum, alloys of magnesium, or a high-impact plastic material such ashigh-impact polystyrene, polyesters, or the like. Other usable hard corematerials may be apparent to those in the art. The core is covered by acoating 13.

A bowling pin base member 14 is secured to the bottom of the pin througha central bore in core 12 and is held in place by a mass of plasticmaterial 15 solidified in situ. The amount of plastic material 15 may beadjusted to give proper balance to the bowling pin. A top pin plug 16 issecured by adhesives or the like in a central bore in the top of the pincore 12. Coating 13, base 14, and top plug 16 define a continuous outersurface corresponding to the outer surface configuration of a regulationbowling pin.

It is common in the art to refer to the various portions of a bowlingpin in terms of the head, neck, shoulder, belly, base or the like. Inthe drawings, the general neck area is shown within the bracketindicated by reference numeral 17 while the general shoulder, belly andbase areas are generally bracketed and indicated by reference numerals18, 19 and 20 respectively. These portions of the bowling pin will bereferred to hereinbelow.

Core 12 is of a usual core configuration above the outward deviation atthe bottom of the neck or top of the shoulder area indicated generallyby reference numeral 23. The normal core configuration for the pin coreis also included in the central belly area between ridges identified byreference numerals 24 and 25. Between reference numerals 23 and 24 thepin core tapers slightly to a weakened or flexible thin area indicatedat 26 and from area 26 the core tapers back to its normal thickness atridge 24. Also, below ridge 25 the core tapers to a weakened or flexiblethin area shown generally by reference numerals 27 and then tapers backto its usual thickness in the base area of the core structure. Theweakened areas 26 and 27 are circular areas extending around the pincore, respectively above and below the impact region of the core belly,and can be the thinnest portions of the core, e.g., as in the formillustrated. The weakened areas permit flexing of the impact regionunder impact conditions, the core generally flexing inwardly fromweakened areas 26 and 27 under the impact and thereafter returning toits original condition. The weakened areas 26 and 2'7 may be formed byslight thinning of the core wall above and below the impact area of thebelly, and said areas may function as hinges from which the belly flexesinward under impact. Beyond these thinner weakened areas the corereturns to its usual configuration.

Coating 13 is a resilient coating material and is preferably anelastomeric composition. The coating may be composed, for example, ofparts by weight of a resin marketed under the tradename Adiprene L-lOO,9 parts by weight of castor oil and 3.2 parts by weight of1,2-butane-diol. The Adiprene resin is a polyurethane resin and consistsof a linear polymer of 1,4-butane-diol and toluene diisocyanate (e.g.2,4-toluene diisocyanate). Other suitable coating compositions includesuch synthetic rubbers as butyl rubber; natural rubber may also beuseful as an elastomeric coating material.

Such resilient coating materials are merely illustrative of coatingmaterials which may be used to provide coated articles in accordanceherewith. It is to be understood that any coating material havingsufficient elasticity to be formable or deformable under impact of abowling ball is usable. More advantageously, the coating material shouldbe sufficiently resilient to retain the outer shape of the bowling pinafter repeated impacts. The coating material is soft and more elasticthan the hard core and is preferably resistant to cold fiow. Otherusable coating materials will be evident to those in the art.

The general manufacture of the bowling pin will also be apparent fromthe description of the pin. The core 12 may be cast in one piece byknown techniques or may be formed of spun metal by known metal spinningtechniques. Coating material 13 may be applied to the formed pin core byknown molding techniques as an uncured mixture of resin ingredients andmay thereafter be cured for a time and at a temperture suificient tosolidify the resin mixture, de ending on the elastomeric material used.

For example, the specific coating material of Adiprene L100, castor oiland 1,4-butane-diol, is cured for about three hours at about 285 F. to aShore A 46 hardness. The resulting structure, having the coating curedon the bowling pin core, is then turned for trimming the coatingmaterial to a size slightly smaller than the regulation bowling pinsize. An outer protective coating 13a is then applied to bring thebowling pin up to regulation size. The coating 13a functions to protectthe pin against discoloration, eg. by dirt, and may serve to reduce thecoeiiicient of friction on the outer pin surface. The outer coating 13amay be a conventional plastic coating for bowling pins, e.g.nitrocellulose or ethylcellulose lacquers, cellulose acetate and/ orbutyrate, polyurethane lacquer, etc.

The bowling pins of the present invention may be handled and used in thesame manner as the maple core bowling pins. Under impact during the gameof bowling, the flexibility of the pin provided by the core weakness inthe belly area permits the ball to travel further into the pin forincreased contact time. Such increased contact time greatly lessens oreliminates the scoring weakness in both the thin and heavy-hit areas,which weakness appears to be inherent in hollow, metal core bowlingpins. In addition, the longer contact time permits transfer of the forcelfrom the ball impact over a longer period of time for improveddurability and improved sound characteristics.

We claim:

1. A bowling pin comprising a hollow metal core and a resilient coatingover said core bringing said core up to regulation bowling pin size,said hollow metal core comprising a thick metal core extending from thetop of the pin downward through at least the major portion of the neckregion of the pin, a tapering core wall extending thence downward andthinning to a first relatively weaker portion above the plane of impactpoints of core, the core wall thence tapering to a thicker portion atthe impact region of the belly of the core, said wall thence thinningbelow the impact region to a second relatively weaker portion and saidwall thence thickening from said second weak portion to the base of thepin core, said first and second weak portions being thinner than anyother portion of the pin core wall so that when the pin is impacted by aball between said first and second weak portions, the ball impact timeis increased by virtue of the presence of said first and second weakportions.

2. A bowling pin comprising a hollow, generally rigid, resilient coreextending from an impact belly region into a lower base region and anupper shoulder region and including a relatively weakened, flexible andresilient portion of said core in the belly region on either side of abowling ball impact plane contiguous with the remainder of said core,said weakened portions being resilient and suficiently weakened toincrease the amount of flexing of the belly area and thereby increasethe ball impact contact time of a ball impacting at said plane, and aresilient coating on the exterior of said core, each of said weakenedportions having a wall thickness less than the wall thickness of theadjacent portions of the core in the base and shoulder regions.

References Cited UNITED STATES PATENTS 2,166,950 7/1939 German et al.273-82 2,944,821 7/1960 Mason 27382 3,138,380 6/1964 Satchell et al.27382 3,141,672 7/1964 Unterbrink 273-82 3,241,835 3/1966 Satchell et a127382 DELBERT B. LOWE, Primary Examiner.

2. A BOWLING PIN COMPRISING A HOLLOW, GENERALLY RIGID, RESILIENT COREEXTENDING FROM AN IMPACT BELLY REGION INTO A LOWER BASE REGION AND ANUPPER SHOULDER REGION AND INCLUDING A RELATIVELY WEAKENED, FLEXIBLE ANDRESILIENT PORTION OF SAID CORE IN THE BELLY REGION ON EITHER SIDE OF ABOWLING BALL IMPACT PLATE CONTIGUOUS WITH THE REMAINDER OF SAID CORE,SAID WEAKENED PORTIONS BEING RESILIENT AND SUFFICIENTLY WEAKENED TOINCREASE THE AMOUNT OF FLEXING OF THE BELLY AREA AND THEREBY INCREASETHE BALL IMPACT CONTACT